What is nipples poking through?

Nipples poking through is a common phenomenon in which the nipples become visibly erect and protrude through clothing. This can happen due to a variety of reasons, including cold weather, stimulation, or arousal. For some people, nipples poking through can be uncomfortable or embarrassing, while for others, it may be a desirable or sexy trait. Nipples poking through can occur in people of any gender and is not necessarily a sign of a medical problem. However, persistent or painful nipple protrusion should be evaluated by a healthcare professional.